1. Field of the Invention
The present invention concerns an apparatus for preventing incontinence and a part of this apparatus which then interacts with a second part and features a fixing device for immovable implantation in body tissue. The part of the apparatus which is to prevent incontinence features a tubular body with a first longitudinal guiding element inside. Connected to the tubular body is a tube-like retaining element which features a second elongated guiding element inside. This ends in a finish in an axial direction on its opposing side to the tubular body. The tube-like retaining element is formed as a reversible stretchable and compressible metal grid which features a polymer covering, together with which it is kept air- and liquid-tight at the finish on the one hand and in the vicinity of the transition to the pipe-like body on the other.
2. Background Information
The term incontinence basically means the inability to retain something. In terms of the present invention this can, for example, be aconuresis. Such an involuntary urine loss is definitely a frequently occurring illness which can have various causes. The general term aconuresis is therefore just the generic term for very different types of illness which can be differentiated and defined by means of their causes. In addition to incontinence caused by stress and pressure, motoric and sensoric urge incontinence are also known. These should in turn be distinguished from obstructive overflow incontinence and functional overflow incontinence, supra-spinal and spinal reflex incontinence or extraurethral incontinence as further causes of incontinence.
With regard to stress incontinence, an apparatus for controlling bladder function manufactured by the Uromedica company has become known which basically consists of two small implantable balloons. These are implanted under the skin next to the bladder during a short surgical procedure. The expansion of the balloons should protect against involuntary urination by compressing the urinary bladder. The natural passing of water is thus not inhibited as the balloon size is set so that for the purposes of urination, normal bladder pressure is sufficient to cause the bladder to be emptied. It should still be possible for a doctor to modify the fill quantity of the two balloons after implantation.
An apparatus of this kind has become known through WO-A-98/56311. WO-A-98/56311 describes an expandable apparatus for preventing aconuresis in which a tubular guide or conduit is connected to a balloon whose circumference can be modified and which is therefore adjustable. The tubular guide penetrates the balloon axially in such a manner that the guide extends into and projects out of the balloon. The respective joints between the conduit and the balloon are sealed liquid-tight, for example with silicone. Instead of sealing with silicone or a comparable chemical or polymeric adhesive, ultrasonic welding is also disclosed as a possible sealing technique.
A first passage which runs through the pipe-shaped conduit in an oblong direction ends within the balloon and opens out inside the same. This passage serves to fill the balloon, for example with a liquid, and thus expand it according to requirements, or to withdraw fluid and thus reduce the size of the balloon.
A further passage may be provided which serves to insert the apparatus in the vicinity of the urethra in a human body. This passage accordingly ends with an opening at the end area of the guide which extends beyond the balloon and into the body. This passage's further opening in the guide is located in the area between the balloon and its proximal end.
For one thing, chemical compounds are specified as materials for the balloon which are themselves capable of forming a seal with the tubular guide in the areas of contact. Compounds such as cross-linked silicone gel, polyvinylpyrrolidone and karaya gum are named. In addition to the embodiment of the expandable apparatus with a first passage with which the balloon can be filled or emptied as already explained, WO-A-98/56311 also elucidates that the balloon wall can also be pierced with a coreless hollow needle and filled or emptied in this manner. A biologically compatible non-elastically restorable elastomer or an appropriate polymer mixture of polyurethane, polymers such as polyethylene, polytetrafluoroethylene (PTFE), polystyrene or polyetheretherketone (PEEK) are named as further materials for the balloon.
The balloon wall can additionally feature reinforcing structures. For this purpose, the balloon is double-walled and the reinforcing structure is situated in between the walls. It can consist of fibres made of polyester, nylon, polypropylene, polytetrafluoroethylene (like TEFLON) or other polymers which feature a high degree of hardness or a high hardness modulus. The fibres may form a net which is woven into a supporting structure which is arranged between the walls of the balloon. In one embodiment, the fibres can be less elastic than the wall itself.
The woven support structure then features a loose fibre weave to permit extension or diminution of the balloon walls.
On the other hand, the fibres of the reinforcing structure can also be mainly non-elastic and woven, whereby the fibres are then knotted to also permit expansion or contraction of the balloon walls.
The reinforcing structure also has the additional task of holding back particles let into the balloon which can be used to expand it in place of a fluid so that they cannot leak out into the vicinity of the balloon. The fibres woven into the support structure can be equipped with a waterproof ripstop function. This means that drops which may form when the hollow needle enters the balloon for filling or emptying can also be absorbed.
With regard to the particles which can be used instead of or together with a liquid to fill the balloon, WO-A-98/56311 cites various examples of particles which by nature of their size can be injected into the balloon by means of a hollow needle in order to then enlarge their diameter within the balloon so that the balloon is expanded. One example of such particles features a core with numerous arms pointing away from it. These particles pass through the hollow needle in a compressed state and expand after entering the balloon. Other such particles can feature a pipe-shaped, elongated structure in order to pass through the hollow needle. The elongated structure then subsequently prevents the particles from flowing back through the needle or the opening in the balloon which forms when the hollow needle is withdrawn.
Further embodiments of particles can consist of hydrophilic material such as polyvinylpyrrolidone, polyethylene glycol, carboxymethyl cellulose or hyaluronic acid which expands inside the balloon.
PCT/EP2010/003757 has made a further apparatus for preventing incontinence known with which instead of the balloon from the previously described state of the art, a tube-like retaining element in the form of a reversible expandable and compressible metal grille is deployed.
This metal grille features a polymer covering and is kept fluid- and watertight on a tubular body in the form of a tubular, flexible tube. The metal grille may feature a diamond pattern whereby the diamonds in a compressed state are formed as slits which preferably feature an extension in the longitudinal direction of the flexible tube of a tubular retaining element connected to the tubular body.
This tubular body serves mainly to bring the retaining element designated as a metal grille to the location in the urethra from which the bladder function can be effectively and practically controlled.
The pipe-shaped, flexible tube is formed as a fabric-reinforced and/or fabric-braided tube, whereby a single or multiple layer of fabric may be present. The pipe-shaped, flexible tube can also feature metallic reinforcement.
The tubular body in the form of a pipe-shaped, flexible tube can be made as a tubular shrink tube of at least one biologically compatible thermoplastic. The material is then preferably selected from polyolefines, polyvinylchloride, polyvinylidenfluoride, polytetrafluoroethylene and/or Viton. This tube and the tube-like retaining element with the metal grille then merge.
The pipe-shaped shrink tube can also feature metallic reinforcement. This metallic reinforcement and also the reversible expandable and compressible metal grille of the tube-like retaining element are then preferably formed as a sandwich between two plastic layers.
In addition, the tubular body can feature an anti-microbial silver coating or a coating of diamond-like carbon in one of its embodiments.
Unlike WO-A-98/56311, the apparatus for preventing incontinence disclosed in this PCT-application is not filled with a fluid or any other expandable polymeric material but with air at atmospheric pressure in the vicinity of the tube-like retaining element.
The tubular body features a first guiding element in the form of a flexible shaft approximately in its centre with spacers which retain the shaft in the tubular body. In the vicinity of its distal end, this flexible shaft ends in an actuator which for its own part features a mesh positioned distally at the end to permit manual adjustment of the apparatus or adjustment by means of a motor drive.
It is of essential importance for the success of an apparatus for preventing incontinence that the two parts of the apparatus originally precisely implanted in the vicinity of the urethra do not subsequently wander and thus cast doubt on the reliability of the apparatus.
According to PCT/EP2010/003757, fixation of the tubular body and thus of the entire apparatus at the implantation site is made possible in that this tubular body features fixing elements in the form of protrusions such as pimples (knobs), hooks and/or scale-like protrusions which protrude outwards on its surface. These can he formed on the tubular body at regular intervals, for example in rows, or also at irregular intervals, whereby they are generally formed with it in one piece.
Such an arrangement of protrusions of the aforementioned type on the outer circumference of the pipe-shaped body can indeed fulfill the desired retaining function and thus contribute to keeping the implant immovably at the desired position after the surgical procedure, but it has disadvantages during the implanting itself. The reason for this is that due to the protrusions, at least part of the mouldings such as pimples or hooks, the tubular body has a larger circumference which should be avoided if at all possible during a minimally invasive procedure.
On the other hand, with WO-A-98/56311 an expandable inter-vertebral spacer has been disclosed in a completely different technical area, namely that of vertebral column implants. Such inter-vertebral spacers are mainly required in case of a slipped disc if parts of the spinal disc obtrude into the vertebral canal, i.e. the space in which the spinal cord lies. This process causes considerable pain. Treatment is either conservative or, in serious cases, by means of a surgical procedure. The spinal disc is partly or completely removed in the process and a spacer is then introduced between the adjacent spinal discs into which bone grows in order to join both discs to one another in this manner. This leads to spinal stiffening at the site of the procedure. It was a major aim of the aforementioned state of the art to provide an inter-vertebral spacer which requires the minimum surgery possible and thus itself features as small a diameter as possible when implanted. For this reason, WO-A-98/56311 proposed an inter-vertebral spacer with an initial, smaller diameter which can be inserted in the area between the two affected discs and then expanded to a significantly larger diameter. This larger diameter can overlap the initial diameter by three to five times or even more. In this way, optimum filling of the inter-vertebral area is achieved by means of the radial expansion of the disclosed spacer in accordance with the aforementioned state of technology without, however, requiring a correspondingly major surgical procedure.
This is achieved by the aforementioned state of the art in that a small axial tube is provided which features a surface and a proximal and a distal end. The surface of the tube exhibits several slits which define at least two axially displaced extensions in such a way that the extensions extend out of the surface and create a geometry of an expanded spacer when the tube is compressed axially. These axially displaced extensions comprise at least three or four extensions which extend correspondingly from the tube in three or four different directions.
Applied to the inter-vertebral area such an axial tube means that it is first inserted into this inter-vertebral area and then significantly compressed in length, whereby extensions expand laterally in the aforementioned three or four different directions which significantly increase the circumference of the tube and thus fill the inter-vertebral area without a correspondingly large wound being caused by the surgical procedure.
Based on this state of the art, the object of the present invention is therefore to provide an apparatus for preventing incontinence which features the benefits of the apparatus as they are possible with PCT/EP2010/003757 and which simultaneously permits an immovable placement of both parts of the apparatus with the least possible side-effects and with a minimum of invasiveness.